Added network components for blimp text input feature

blimp/client/feature/web_input_feature.h

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef BLIMP_CLIENT_FEATURE_WEB_INPUT_FEATURE_H_
+#define BLIMP_CLIENT_FEATURE_WEB_INPUT_FEATURE_H_
+
+#include <map>
+#include <string>
+
+#include "base/macros.h"
+#include "blimp/client/blimp_client_export.h"
+#include "blimp/net/blimp_message_processor.h"
+
+namespace blimp {
+namespace client {
+
+// Handles all incoming and outgoing protobuf messages for text input
+// of type BlimpMessage::IME. The handling of the message is delegated to the
+// floating WebInputBox.

[nyquist, 2016/03/10 00:57:13]

I guess WebInputbox isn't know by this class, so maybe just refer to the
WebInputFeatureDelegate here?

[shaktisahu, 2016/03/15 23:44:13]

Done.

+class BLIMP_CLIENT_EXPORT WebInputFeature : public BlimpMessageProcessor {

[nyquist, 2016/03/10 00:57:13]

Should there be a test for this class? It doesn't have a lot of external
dependencies, so hopefully shouldn't be too crazy to add one.

+ public:
+  // A delegate to be notified of text input events.
+  class WebInputFeatureDelegate {
+   public:
+    virtual void OnImeRequested(bool show,

[David Trainor- moved to gerrit, 2016/03/14 17:59:41]

Javadoc.  Should we pull hide out to another method?  It feels like input_type
and text aren't relevant in that case, so it's a little weird to have both of
these actions bundled together here.

[shaktisahu, 2016/03/15 23:44:13]

Done.

+                                int input_type,
+                                const std::string& text) = 0;
+  };
+
+  WebInputFeature();

[Khushal, 2016/03/10 07:54:10]

I think the WebInputFeature should be like the compositor and gesture input,
since it is also tied to a render widget. If we are getting requests from an old
widget, then we shouldn't process them.
In fact now that I'm thinking about it, we should have gesture input and text
input tied to a navigation. If we navigate within the same site-instance and the
render widget remains the same, should we be dropping messages from the previous
navigation? +dtrainor

For now, we should add web input like other features in
EngineRenderWidgetFeature on the engine.
On the client, in the BlimpCompositorManager, when a new widget is initialized,
in OnRenderWidgetInitialized, reset any state in the WebInputFeature and hide
it. Make a note of the active render_widget_id so if you receive requests from
the previous widget you can drop them.
The BlimpCompositorManager will need the WebInputFeatureDelegate to send the
text input events to. You can pass it to the BlimpCompositorManager when the
BlimpView builds it.

+  ~WebInputFeature() override;
+
+  // Set the BlimpMessageProcessor that will be used to send BlimpMessage::IME
+  // messages to the engine.
+  void set_outgoing_message_processor(
+      scoped_ptr<BlimpMessageProcessor> processor);
+
+  // Sets a WebInputFeatureDelegate to be notified of all text input messages.
+  void SetDelegate(WebInputFeatureDelegate* delegate);
+
+  // Sends text from Ime to the blimp engine.

[nyquist, 2016/03/10 00:57:13]

Nit: 'IME'

[shaktisahu, 2016/03/15 23:44:13]

Done.

+  void SendImeTextToEngine(const std::string& text);
+
+ private:
+  // BlimpMessageProcessor implementation.
+  void ProcessMessage(scoped_ptr<BlimpMessage> message,
+                      const net::CompletionCallback& callback) override;
+
+  WebInputFeatureDelegate* delegate_;
+
+  // Used to send BlimpMessage::IME messages to the engine.
+  scoped_ptr<BlimpMessageProcessor> outgoing_message_processor_;
+
+  DISALLOW_COPY_AND_ASSIGN(WebInputFeature);
+};
+
+}  // namespace client
+}  // namespace blimp
+
+#endif  // BLIMP_CLIENT_FEATURE_WEB_INPUT_FEATURE_H_